The broad objective of this programatic research continues to be the study of social-affective development in infancy. Current studies emphasize that in human infancy emotional expressions provide a medium of communication between infants and caregivers. Infant facial expressions of emotion are being studied at different ages to determine the developmental onset of various pattern messages. In addition, the ability of adults to recognize these infant emotional signals is also being studied. Possible deviations in signal-operating characteristics are being explored by comparing the expressions of normal infants with those of Down syndrome infants. Deviations in receiver-operator characteristics are being delineated by contrasting populations such as teenage mothers, mothers at risk for child abuse and neglect, and adult females with varying degrees of child giving experience. Studies investigating infants' reactions to the emotional expression signals of their mothers are currently in progress. Normal infants during the latter half of the first year are being studied to assess whether they use their mothers' emotional expressions for regulating their own affects and for coping with uncertain situations. In addition, investigations are contrasting infants reactions to adult emotional signals which are communicated via either facial expressions or vocalic expressions. Finally, we have completed a series of studies assessing the effects of increased hospital contact and separations on the interactions of mothers and fathers with their newborn infant. We have also assessed the effects of variations in eye contact and newborn state on early parental interactions.